Latch guard



June 18, 1957 R. D. PHILPOTT LATCH GUARD Filed Oct. 9, 1953 D. PH/LPOTT/N VEN TOR aEEHLf/e,

HUBNER,

' WORREL s HERZ/G r Afro/wem fwm' United States Patent The presentinvention relates to latches for doors, Windows, hatches and otherclosure members and more particularly to a latch guard for preventingunauthorized Y releasing of such latches.

As is well known, the conventional closure' members of the characterreferred to close against jambs and are releasably held in closedposition by latch bolts. Because of normal clearance or space betweenclosure members and their frames the latch bolts are accessible forretraction by a knife blade or other ilat instrument inserted betweenthe closure members and their frames and worked against the bolts. Manydevices have been constructed to guard against this danger but few, ifany, of the known structures are designed for attachment as auxiliarymembers to previously installed closure members and their latches.Stated otherwise, most conventional latch guards are integral portionsof their respective latches. With these devices much modification of thedoor and jamb is necessary to eifect proper installation. Furthermore,many of the known guarding devices .are bulky and mar the appearance ofthe door.

Of even greater functional signicance, conventional latch guards whichare integral with their respective latches are rigidly mounted withtheir latches on either closure members or frames for the closuremembers. The greatest hazards of having latches picked or jimmied areencountered as the closure members shrink from their respective framesbecause of wood seasoning, climatic changes, or the like so as to makethe bolts of the latches accessible between the closure members andframes. The latch guards which are integral with their latches do notsuccessfully adjust to closure shrinkage or expansion inasmuch as suchguards are either mounted on the closure and thus move away from theiradjacent frame as the closure shrinks or are mounted on the frame andare rendered ineffective by closure shrinkage therefrom.

It is therefore an object of the present invention to provide a latchguard which automatically compensates for shrinkage and/ or swelling ofclosure members in their frames so as to provide dependable guardingeven through excessive variations in relative sizes of closure membersand their frames are encountered.

Another object is to provide an improved latch guard includingcooperative elements, one thereof being mountable on a closure memberand another on a frame for the closure member so as to overlap inshielding relation to the latch of the closure member during all normalranges of shrinkage and/ or swelling of the closure member.

Another object of the invention is to provide a latch guard that canconveniently be installed on any conventional closure member withoutaltering the design thereof.

Another object of this invention is to provide a latch guard for closuremembers of the nature described which is invisible from the exterior ofthe closure member when it is closed.

Another object is to provide a latch guard for door latches which isself-adjusting under varying climatic conditions, and will operateregardless of expansion and Patented June 18, 1957 ice contraction ofthe door or jamb within reasonable limits.

Another object is to provide a latch guard of the nature described whichaids in centering closure members in their frames in the event ofdeparture from desired position by closure member settling or framedistortion.

Another object is to provide a latch guard which aids in increasing thebite of the latch bolt when shrinkage has occurred.

These and other objects of this invention will become more apparent withreference to the following description and accompanying drawings, inwhich:

Fig. l is a fragmentary elevation of a door, representative of closuremembers generally, in closed position in a frame therefor and showing aconventional latch adapted releasably to retain the door in closedposition, all of which constitute exemplary operational environment forthe latch guard of the present invention a portion of which is shown indash line. v

Fig. 2 is a section taken on line 2 2 of Fig. l.

Fig. 3 is a fragmentary edge elevation of the door showing the latchthereof and a portion of the latch guard of the present invention.

Fig. 4 is a fragmentary edge elevation of the door frame showing a latchkeeper mounted therein and a portion of the latch guard of the presentinvention having a cooperative relation with the portion shown in Fig.3.

Fig. 5 is a section taken on line 5-5 of Fig. 1. e

Fig. 6 is a section taken on line 6 6 of Fig. l.

Fig. 7 is an exploded view of cooperative elements o the latch guard ofthe present invention.

Referring in greater detail to the drawing: v

The latch guard of the present invention consists of a plurality ofcooperative flat plates 10 and 12 of two different sizes. siredplurality may be utilized as suggested by the functional requirementsbut the full -advantages desired are not attained unless at least twocooperative plates are utilized.

The plate 12 is adapted to nest within the plate 10 in substantiallyco-planar relation therewith. The outer plate 10 is conveniently formedfrom a substantially rectangular blank of sheet metal or the like havingopposite end edges 13 and side edges 14. An edgewardly disposed notch 15is formed in one of the side edges 14 leaving ears 16 at opposite' endsof the plate integrally interconnected by a leg 17 longitudinally of theplate.l The ears provide facing, upwardly and downwardly disposed, edges18 and 19, respectively. The deined form of the platey 10 is readilyobservable in Figs. 3, 5 and 7.

The inner plate 12 is conveniently formed of a trapezoidal blank ofsuitable sheet material having opposite end edges 20 and substantiallyparallel side edges 21. A notch 22 is formed in one of the side edges 21to receive the bolt of a latch, as will be subsequently described. Theend edges 20 converge toward the side edge opposite that in which thenotch 22 is provided at substantially the same angle of convergence asthe angle of divergence of the edges 18 and 19 of the outer plate 10. Itwill be noted in Figs. 5 and 7 that the inner plate 12 is looselycomplementarily fitted to the outer plate 10. So formed, the inner platehas ears 23 at opposite ends thereof integrally interconnected by a leg24 longitudinal of the plate. For mounting convenience, counter-sunkbores 2S are formed through the ears 23 of the plate 12 and through theears 16 of the plate 10. v

Inasmuoh as various thicknesses of the plates 10 and 112 are desiralblein dilering environments, shim plates 10 similar to the outer plate 10and shim plates V12 similar to the inner plate 12 are provided. When aplate thicker than plate 10 is desired, any desired number of shimplates 10' are utilized in stacked relation therewith. Sim- As will soonbecome apparent, any de-` ilarly, greater thickness is attained byemploying any desired number of shim plates12 with the plates 12.

Referring now to Figs. 1 to 6, there is seen the application of plates1f) and 12 to a closure member, such as a door 2,6, and its associatedframe 28. Fig. 3 shows the larger plate 10 vertically mounted andattached by means of screws y29 positioned in the bores 2S and fastenedinto the edge of the door. The plate is mounted directly on the door ori-n the event that the door lock is provided with a latch plate, as 3f),it is mounted over the latter. In any case, the plate 1f) is not flushwith the doors edge but-rather extends radially outwardly ltherefromitl-s thickness in the direction -of the frame `.28as best seen in Figs.l, 2 and 6. The outside edge of intermediate portion 17 is, however,preferably flush with the outside face 31 of the door. Furthermore,plate 10 is mounted so that the notch 1S thereof partially surrounds, orspans, the bolt 32 ofthe door lock, as seen in Pig. 3.

With reference to Fig. 4, the smaller plate 12 is mounted in a mannersimilar to plate 1f) but on the frame 23. Thesquared inner notch 22 ofthis plate surrounds the keeper or latch bolt opening 36 in the frameand the outer edge 21 of the-intermediate portion 24 of the plate isarranged to face in the direction of the strike plate 37. As above, thesmaller plate 12 extends outwardly from the frame 28 in the direction ofthe edge of the door 26. The plates are vertically aligned on theirrespective door and frame so that when the door closes in the frame, asrepresented in Fig. 5, the plates overlap in the nesting relationdescribed above. l

The above will be more clearly apparent upon the explanation of the useof the lock safety device described above. It is assumed that the door26 .and frame 23 desired to be protected are provided with plates in the`manner shown in Figs. 1 to 6, both inclusive. Whenever fthe door isclosed the notch or cut-out portion of tl e plate 10 mates with theouter peripheral edge of plate 12 in the co-planar relation shown inFig. 5. With the door thus closed and the plates so mated, access to thebolt 32 from between the door and frame in the direction of the arrow inFig. 6 is prevented. This is true because the plates are designedoverlappingly to fill the space between the door and frame arou-nd thelock bolt 32.

Due .to this overlapping relation of the plates, a certain amount ofshrinkage or expansion may be allowed for and accommodated by theplates. As is most evident from Fig. 6, lateral or transverse movementof the door does not affect the mating of the plates and the bolt is notexposed unless the door or frame shrinks an amount greater than thewidth of one of the plates, assuming that plates 10 and 12 are not inuse. in the event that it is indeterminate from the outset whethershrinkage or expansion will occur, the plates are mounted in offsetrelation a-nd instead of a full overlap as shown, are only partiallyoverlapped. When so mounted, both shrinkage and expansion may occur toan extent approximately equal to one-half the wid-th of the plateswithout destroying the protective effect of the plates.

.Furthermore, if the space between door and frame when the door isclosed, is greater than the combined thickness of the plates, aduplicate of either plate such as 1d and/ or 12 is mounted beneath itscompanion plate effectively increasing its width and filling the space.

An add-ed advantage of the safety device when shrinkage occurs is thatof increasing the bite ofthe bolt thereby aiding in latohing thereof byengagement with the portion 24 of the plate 12.

With the device of this invention, operation of the door or otherclosure member is not changed in any marmer nor is the structure of thedoor modified to such an extent that the appearance of the door ismarred. Because of the location of plates, the latch guard is normallysubstantially invisible from the exterior of the door when the door isclosed.

An additional advantage resulting from the particular construction ofplates 10 and 12 is the camming effect which edges 18 and/ or 19 exerton edges 20. Since closure members and associated frames often becomemisaligned due to improper hanging @if the door or sagging thereof,proper operation is sometimes difficult. If closed, a misaligned doorcauses the bolt to be out of line with the keeper opening and thus thedoor will not properly latch and remain closed. This invention preventsor minimizes this undesirable condition.

When the door and frame are in preferred elevational relation, forconvenience designated as a neutral position, plates lil and 12 mate asdescribed, generally with a small clearance therebetween, as at 40.However if door 25 moves up or down relative to this neutral position,the plate 1f) will be offset slightly in a vertical direction from plate12. When the door is closed in the frame the edges 18 and/or 19 camagainst the edges 20 to urge the door up or down into its propervertical or neutral position, thereby permitting the bolt to fit in thekeeper opening.

'Since the lat-ch guard of this invention is intended to protect thelatch bolt from unauthorized tampering, it is apparent that theintermediate portion 17 of plate 10 must be disposedV between the boltand the outside surface of the door, thus surrounding or shielding thelock bolt from the outside. Furthermore, since plate 12 properly fitswithinplate 1f) in only one manner, namely with the outer peripheraledge nested wit-hin the cutout portion of plate 1t), it is apparent thatplate 1,2 must also have its portion 24 disposed between the boltopening and the outside of the door.

Therefore, when door 26 opens outwardly toward A in the manner shown inFig. 2 and the outside of the door is at A, the larger plate 10 will beattached to the door, and the smaller plate 12 to the frame, in themanner illustrated. However, when the outside of the door is at B, theoutside edge of intermediate portion 17 must face in the direction B,thereby to shield bolt 32 from access in that direction, as between thejamb 42 and the frame. With the door opening in the same direction (thatis toward A), it is necessary to reverse the location of the plates 10and 12 so that proper mating in the overlapping position will beeffected. Thus plate 1@ is mounted on the frame and plate 12 is mountedon the door, the latter, of course, having the outside edge ofintermediate portion 24 facing in direction B.

Although the invention has been herein shown and described in what isconceived to be the most prac-tical and preferred embodiments, it isrecognized that departures may be made therefrom within the scope of theinvention, which is not to be limited tothe details disclosed herein butis tobe accorded the full scope of the claims so as to embrace any andall equivalent devices and apparatus,

Having described my invention, what I claim as new and desire to secureby Letters Patent is:

1. In a door having a latch bolt extending outwardly therefrom, and aframe adapted to receive the door and having an openingrfor receivingthe bolt; a safety device for preventing jimmying of the bolt comprisinga first flat plate mounted on the frame around the opening havingopposite plane surfaces and a peripheral edge, the peripheral'edgedefining opposite end and side edges, and a second flat plate mounted onthe door around the bolt having opposite plane surfaces and a peripheraledge, the peripheral edge defining opposite end and side edges, a sideedge of one of said plates having a substantially U-shaped cut-outportion therein defined by an inner longitudinal edge and facingtransverse edges, the transverse edges being relatively divergentoutwardly of the inner` edge, the end edges of the other of said platesbeing divergent from one side edge thereof, the end edges and said oneside edge of said other plate being complementarily fitted against thetransverse edges and inner edge, respectively, ofthe cut-.out portion ofsaid one plate when the door is received in the frame, the transverseedges of the cut-out portion and the end edges of said other plateacting as a camming means for guiding the plates to nested relation whenthe door is closed and also guiding the door into predeterminedelevational position in the frame when the door is in a closed position.

2. In a door having a latch bolt extending outwardly therefrom, and aframe adapted to receive the door having an opening for receiving thebolt when ,the door is closed, the door and frame providing flat edgesaround the bolt and the opening and adapted to lie in spaced facingrelation when the door is closed, a latch guard for the bolt comprisingan outer ilat plate having opposed plane surfaces and of substantiallyuniform thickness throughout, the plate providing one side edge having asubstantially U-shaped notched portion therein and being fitted with oneof its plane surfaces in flush relation against the flat edge of thedoor with the notched portion thereof disposed around the latch bolt andfacing toward the frame when the door moves toward closed position, aninner plate having opposed plane surfaces and of substantially the samethickness throughout as the outer plate, the inner plate providingopposite end and side edges, the end edges and one of the side edges ofthe inner plate defining a substantially U-shaped contour adapted tomate with the U-shaped notch in the side edge of the outer plate, theother side edge of the inner plate being notched, the inner plate beingfitted with one of its plane surfaces in iiush relation against the atedge of the frame with the notched side edge thereof disposed around thebolt receiving opening of the frame and facing in the same direction asthe notched portion of the outer plate, said plates being elevationallyaligned when the door is closed in the frame with the U-shaped side andend edges of the inner plate fitting within the U- shaped notched edgeof the outer plate and both plates lying in substantially, Vthe sameplane around the latch bolt.

3. In a door having a latch bolt extending outwardly therefrom, and aframe adapted to receive the door having an opening for receiving thebolt when the door is closed, the door and frame providing iiat edgesaround the bolt and the opening and :adapted to lie in spaced facingrelation when the door is closed, a latch guard for the bolt comprisingan outer flat plate having opposed plane surfaces and of substantiallyuniform thickness throughout, the plate providing one side edge having asubstantially U-shaped notched portion therein defining an inner edgeand outwardly divergent camming edges, the outer plate being fitted withone of its plane surfaces in ush relation against the flat edge of thedoor with the notched portion thereof disposed around the latch boltIand facing toward the frame when the door moves toward closed position,an inner plate having opposed plane surfaces and of substantially thesame thickness throughout `as the outer plate, the inner plate providingopposite end and side edges, the end edges and one of the side edges ofthe inner plate defining a substantially U-shaped contour with the endedges forming outwardly divergent camming edges relative to said oneside edge adapted to mate with the Urshaped notch in the side edge ofthe outer plate, the other side edge of the inner plate being notched,the inner plate being fitted with one of its plane surfaces in flushrelation against the flat edge of the frame with the notched side edgethereof disposed around the bolt receiving opening of the frame andfacing in the same direction as the notched portion of the outer plate,said plates being elevationally aligned when the door is closed in theframe by camming action between said camming edges so that the U-shapedside and end edges of the inner plate fit within the U-shaped notchededge of the outer plate and both plates lying in substantially the sameplane around the latch bolt.

4. ln a door having a latch bolt extending outwardly therefrom, and aframe adapted to receive the door having an opening for receiving thebolt when the door is closed;'a safety dev-ice for preventing jimmyingof said bolt comprising a rst at plate mounted on the frame around theopening having opposite plane surfaces and opposite end and side edges,and a second flat plate mounted on the door around the bolt havingopposite plane surfaces and opposite end and side edges, a side edge ofone of said plates having a substantially U-shaped cut-out portiontherein, and the end edges and a side edge of the other plate having asubstantially U-shaped contour complementary to said cut-out portion andreceived in said cut-out portion when the door is in closed positionthereby aligning corresponding opposite surfaces of said plates insubstantially co-planar relation around the bolt.

5. A latch guard for shielding the bolt of a door cornprising a lirstiiat plate having opposite plane surfaces and opposite end and sideedges adapted to be secured 4to the frame for the door, and a secondiiat plate also having opposite plane surfaces and opposite end and sideedges adapted to be lsecured to the door around the bolt, the side edgeof one of said plates defining therein a substantially trapezoidaledgewardly disposed notch having an inner longitudinal edge portion andlateral edge portions, the end edges and one of the side edges of theother of said plates having a substantially trapezoidal configurationcomplementary to said notch, the lateral edge portions of said notch andthe end edges of said other plate acting as a camming means whereby uponclosing the door into the frame the plates rest in substantial co-planarrelationship and guide the door into .predetermined position in theframe.

References Cited in the le of this patent UNITED STATES PATENTS 915,873Mosher Mar. 23, 1909 1,092,946 Page Apr. 14, 1914 1,853,456 Ross Apr.12, 1932 2,631,881 Trachsler Mar. 17, 1953

